The word church is an incorrect substitute for the Greek word ekklesia, which literally means "the called out ones".
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The Origin Of The Word "CHURCH"
Act 7:37-38 This is that Moses, which said unto the children of Israel, A prophet shall the Lord your God raise up unto you of your brethren, like unto me; him shall ye hear. (38) This is he, that was in the
ekklesia in the wilderness with the angel which spake to him in the mount Sina, and with our fathers: who received the lively oracles to give unto us:
1Cor 1:2 Unto the
ekklesia of God which is at Corinth, to them that are sanctified in Christ Jesus, called to be saints, with all that in every place call upon the name of Jesus Christ our Lord, both theirs and ours:
Kuriakon actually means “pertaining to the lord.” It is used twice in scripture: 1 Cor 11:20 The “ Lord’s [ kuriakon]supper;” and Rev 1:10, the “ Lord’s [ kuriakon] day.” In those passages it is the supper belonging to the Lord and the day belonging to the Lord respectively.
Kuriakon, kirche, and church, all meant simply a religious building originally used by pagans and later used by Christians following pagan customs. Christians originally didn’t use buildings, which distinguished them from the pagans whose focus was on building, statues, ritual and physical objects. [
Copied from The Origin Of The Word Church at scribd.com]
Throughout the Greek world and right down to NT times (cf. Acts 19:39), ekklesia was the designation of the regular assembly of the whole body of citizens in a free city-state,
“called out” (Gr, ek, “out,” and kalein, “to call”) by the herald for the discussion and decision of public business (Lambert 1929, 651).